1. Field of the Invention
The present invention relates to an inflator of an air bag device for vehicles, and an air bag device for a driver incorporating the inflator. More particularly, the present invention relates to an inflator provided with a mechanism for controlling the direction of ejection of gas, and an air bag device for a driver incorporating the inflator.
2. Description of the Related Art
An air bag device for vehicles is a device for protecting an occupant by extending an air bag when a vehicle comes into collision. The air bag device is provided with an inflator for generating and ejecting gas so .as to extend the air bag.
FIG. 2 is a vertical sectional view of a conventional air bag device for a driver. A retainer 10 in the shape of a plate is provided with an inflator insertion hole 12 for receiving an inflator 14 at the center thereof.
A gas receiving hole 18 of an air bag 16 is disposed concentrically with the hole 12, and a flange 14a of the inflator 14 and the peripheral portion of the gas receiving hole 18 are fixed to the retainer 10 by fitting members such as bolts, rivets and split pins.
The air bag 16 is folded in such a manner as to be extended by the gas ejected from the inflator 14. The air bag 16 is covered with a module cover 22 which is fixed to the retainer 10. When the gas from the inflator 14 is ejected from ejection holes 24, the air bag 16 begins to be extended. The module cover 22 is then torn along a tear line 26, whereby the air bag 16 is largely extended toward the driver.
In an air bag device for a driver, it is favorable for a driver that the air bag 16 quickly and largely extends vertically and horizontally (rightward and leftward in FIG. 2). For this purpose, in a conventional air bag device for a driver, the inflator 14 is projected from the retainer 10 toward the inside of the air bag device, and the ejection holes 24 are provided in the peripheral surface of the inflator 14. When gas is ejected sideways through the ejection holes 24, the air bag 16 quickly and largely extends rightward and leftward in FIG. 2.
In the conventional air bag device for a driver, however, since the inflator 14 projects toward the inside of the air bag device, the thickness T.sub.2 of the air bag device at the portion above the retainer 10 increases by the height of the projected portion of the inflator 14.